3rd biggest US state with an area of 163,696sqmi and biggest in terms of population with 38,802,500 residents

The San Andreas fault (the conservative plate boundary between N. American plate and Pacific Plate) runs through California.

Vunerability

>70% of the population live within 50km of a fault line.

An increasing population has led to buildings being developed on unstable land. This leads to liquefaction during EQs and can also increase the risk of landslides

The coast is very developed meaning many people are at risk from Tsnamis

20% of residents live below the poverty line. These people have the lowest capacity to cope with disaster

California is a highly developed area with state of the art technology that predicts disasters (e.g seismographs) as well as prevent them (e.g. building reinforcement, disaster training)

It has a massive economy which means, combined with it's advanced prevention measures, that losses are mainly economic rather than human

Earthquakes

The San Andreas fault is a conservative plate boundary which runs through California making it very earthquake prone

EQs occur when the parallel plates snag creating a build up of pressure which is suddenly released sending seismic waves in all directions.

These EQs are usually shallow in California making them more destructive

Facts

These is a high chance that a 7.0+ magnitude EQ will hit San Francisco bay in the next 25 years

15-20 4.0+ magnitude EQs each year.

More than 70% of California's population live within 50km of a fault line

California has lots of building on unstable land which causes severe liquefaction

Loma Prieta EQ- 1989

A magnitude 7.1 struck in the Santa Cruz mountains 60 miles south of San Fransisco at 5:04 pm on 17 October 1989

A magnitude 5.2 aftershock struck 37 mins after the main EQ

63 people were killed (mainly by a collapsed freeway); 13 750 were injured; 1081 homes were destroyed; 23 408 homes were damaged; just under 4000 businesses were destroyed or damaged; total cost US$6 billion

The death toll was low due to the freeways being unusually clear due to the world series baseball game